swatplus-builder 0.4.0

Build and calibrate SWAT+ hydrologic models from a USGS gauge ID — with evidence-backed, claim-governed results.

swatplus-builder

Calibrated SWAT+ models from a single gauge ID — with evidence you can audit.

swatplus-builder builds and calibrates SWAT+ hydrologic models in Python, starting from one USGS streamgage ID. It can be driven by a person or by an AI agent — and either way, the software, not the operator, decides what each result is allowed to claim, through runtime gates, provenance, locked reruns, and evidence-backed claim tiers.

The whole pipeline runs in Python with no desktop GIS — no QGIS, PyQGIS, or the QSWATPlus plugin. GIS work uses WhiteboxTools + rasterio + geopandas, and the SQLite → TxtInOut translation uses the vendored SWAT+ Editor Python API.

📚 Full documentation: https://ai-hydro.github.io/swatplus-builder/ Concepts (claim governance, locked calibration, the evidence bundle), a user guide, the agent/MCP surface, and a CLI/Python/schema reference.

New here? Read QUICKSTART.md. It covers requirements, install, engine/reference-DB bootstrap, the canonical one-command workflow, and how to operate the pipeline through an AI agent (MCP).

The canonical end-to-end path is a single command:

swat workflow run --usgs-id <id> --model-family full \
  --start 2000-01-01 --end 2019-12-31 --warmup-years 3 \
  --calibrate --claim-tier research_grade --json

It builds the model, runs the engine, locks a benchmark, runs gated diagnostic calibration, independently verifies a locked rerun, and writes a machine-readable evidence bundle with explicit allowed/blocked claims. The package — not the agent — decides what may be claimed.

---

Status

Alpha, v0.4.0 — locked-benchmark calibration, 11-tool agent (MCP) surface, container baseline.

• Pure-Python GIS (WhiteboxTools, rasterio, geopandas)
• Automated SWAT+ project generation
• Weather (GridMET / synthetic)
• USGS NWIS observed discharge fetch
• Two-pass outlet evaluation (auto-select → strict-pin)
• NSE / KGE / BFI metrics (evaluate_run — authoritative)
• Locked-benchmark calibration protocol (lock → calibrate → verify)
• pySWATPlus bridge with fail-loud diagnostics artifact
• 11-tool MCP server (swat mcp / docker-compose mcp service)
• Container baseline (Dockerfile + docker-compose)
• Publication-ready figures (7+ types)

See:

• Documentation site — concepts, user guide, agent/MCP, and full reference
• QUICKSTART.md — install, run, and operate via agents
• Honest status — what the system actually claims today (0/11 research-grade)
• ROADMAP.md — phased plan with checkboxes
• PROGRESS.md — running progress journal
• DECISIONS.md — architecture decision records
• docs/AGENT_WORKFLOW.md — implemented negotiate → run → evidence flow
• docs/ARCHITECTURE.md — system architecture

---

Authoritative calibration path

The lock → calibrate → verify chain is the only scientifically defensible route to reported calibration metrics.

1. swat lock-benchmark     # snapshot baseline metrics + alignment CSV
       ↓
2. swat locked-calibrate   # real-engine DDS on CN2 + ALPHA_BF only
       ↓                   # (calls verify automatically unless --skip-verify)
3. metrics reported        # delta NSE/KGE vs locked baseline, independently verified

Rules (enforced by the toolchain):

• Parameters are restricted to CN2 and ALPHA_BF — no silent scope expansion.
• Calibrated metrics are always delta-reported against the locked baseline.
• verify_calibration is mandatory — it re-runs the best solution independently to confirm reproducibility.
• evaluate_run is the authoritative metric source for all reporting.

One-liner for agents:

swat locked-calibrate \
  --benchmark-dir artifacts/locks/usgs_01547700/benchmark \
  --base-txtinout TxtInOut/ \
  --out-dir artifacts/calibration/ \
  --json

Bridge diagnostics (non-authoritative / fail-loud)

The pySWATPlus bridge (swat calibrate --calibration-engine pyswatplus) is a secondary calibration path. When it fails, it writes a structured bridge_failure_diagnostic.json artifact (timestamp, traceback, staged file manifest, failure stage) and exits non-zero. Do not rely on raw bridge objective values for reporting — the bridge metric parity layer redirects all reported metrics through evaluate_run.

If the bridge path fails: check bridge_failure_diagnostic.json under the calibration artifacts directory. The real-engine path (swat calibrate --real-engine or swat locked-calibrate) is the currently reliable authoritative route.

---

Install

# Core only
pip install swatplus-builder

# With GIS stack (recommended)
pip install "swatplus-builder[gis]"

# With HyRiver helpers (USGS gauges, NHDPlus, py3dep, GridMET)
pip install "swatplus-builder[gis,hyriver]"

# Full dev environment
pip install -e ".[all]"

SWAT+ engine binary is not a pip dependency — bring your own swatplus_exe and mount it at runtime.

---

Container quick-start

# Build image
docker compose build

# Check runtime health (no binary mounted — expect degraded)
docker compose run --rm swat health --json

# Run with binary mounted
SWATPLUS_BIN_DIR=/path/to/swatplus_dir docker compose run --rm swat version
SWATPLUS_BIN_DIR=/path/to/swatplus_dir docker compose run --rm swat health

# Run locked-calibrate inside container (artifacts persisted to ./artifacts/)
SWATPLUS_BIN_DIR=/path/to/swatplus_dir docker compose run --rm swat \
  locked-calibrate \
  --benchmark-dir /data/artifacts/locks/usgs_01547700/benchmark \
  --base-txtinout /data/TxtInOut \
  --out-dir /data/artifacts/calibration \
  --json

# MCP stdio server (for agent connections)
SWATPLUS_BIN_DIR=/path/to/swatplus_dir docker compose run --rm mcp

Volume mounts (configured in docker-compose.yml):

• ./artifacts → /data/artifacts (persisted run/calibration artifacts)
• $SWATPLUS_BIN_DIR → /opt/swatplus (SWAT+ engine binary directory, read-only)
• $SWATPLUS_DATASETS_DIR → /data (reference datasets SQLite)

---

CLI (swat)

# Version with git SHA
swat version
swat version --json   # machine-readable

# Runtime health check (deterministic exit codes: 0=healthy, 1=degraded, 2=unhealthy)
swat health
swat health --json

# Full pipeline (one-liner for existing TxtInOut)
swat run --txtinout TxtInOut/ --threads 4

# Locked-benchmark protocol
swat lock-benchmark \
  --txtinout TxtInOut/ \
  --observed-csv observed.csv \
  --out-dir artifacts/locks/my_basin \
  --basin-id usgs_01547700

swat locked-calibrate \
  --benchmark-dir artifacts/locks/my_basin/benchmark \
  --base-txtinout TxtInOut/ \
  --out-dir artifacts/calibration/my_basin \
  --parameters CN2,ALPHA_BF \
  --json

# Multi-basin readiness table
swat readiness-table --locks-root artifacts/locks/ --json

# Inspect persisted run metadata
swat inspect <run_path>

# Benchmark validation over a basin suite
swat validate --basins basins/curated_v1.json

# Launch MCP server (stdio)
swat mcp

Exit-code contract

Code	Meaning
0	Success
1	Runtime / engine failure (external tool failed, bridge error)
2	User / config error (bad arguments, missing required files, unknown parameters)
3	Quality gate failure (e.g., --min-improvement-nse not met)

---

MCP server — 11-tool surface

pip install "swatplus-builder[mcp]"
swat mcp   # stdio transport

MCP client config (Claude Desktop / Cursor / any MCP host):

{
  "mcpServers": {
    "swatplus-builder": {
      "command": "swat",
      "args": ["mcp"],
      "env": {
        "SWATPLUS_EXE": "/usr/local/bin/swatplus_exe",
        "SWATPLUS_BUILDER_ARTIFACTS": "/data/artifacts"
      }
    }
  }
}

Tool tiers:

Tier 1 — Basin workflow (8 tools): build_project, run_basin, calibrate, propose_parameters, compare_runs, query_artifacts, diagnose_failure, validate

Tier 2 — Benchmark / readiness (3 tools): lock_benchmark, locked_calibrate, readiness_table

---

Soil fidelity flags

Every run persists soil realism metadata in metadata.json:

• soil_mode: high_fidelity | fallback | synthetic
• pct_fallback_soils: fraction of basin polygons using fallback soil profiles

Fallback usage >25% emits a warning. Threshold configurable via SWATPLUS_SOIL_FALLBACK_WARN_THRESHOLD. Generated figures include a visible quality annotation for fallback/synthetic runs.

Use swat inspect <run_path> to view persisted metadata.

---

Agent-facing API

from swatplus_builder.tools import (
    build_watershed,
    create_hrus,
    generate_swat_project,
    run_swat,
)

ws = build_watershed(
    dem_path="data/dem.tif",
    outlet=(-77.123, 41.456),
    stream_threshold_cells=500,
    workdir="runs/marsh_creek/",
)

hrus = create_hrus(ws, "data/nlcd_2019.tif", "data/gnatsgo_mukey.tif")
project = generate_swat_project(ws, hrus, "data/weather/", "2000-01-01", "2010-12-31", "marsh_creek_v1")
result = run_swat(project, threads=4)

Locked-benchmark API (for direct Python use):

from swatplus_builder.calibration.locked_benchmark import (
    lock_benchmark,
    calibrate_against_lock,
    verify_calibration,
    build_readiness_table,
)

lock = lock_benchmark(txtinout_dir, obs_series, out_dir, basin_id="usgs_01547700", outlet_gis_id=1)
evidence = calibrate_against_lock(lock, base_txtinout, out_dir, parameters=["CN2", "ALPHA_BF"])
result = verify_calibration(lock, evidence.best_solution_json, base_txtinout, out_dir)
rows = build_readiness_table(locks_root)

---

Phase 3E calibration evidence baseline

As of 2026-04-25, the locked real-engine calibration protocol has been run and independently verified on two USGS basins (CN2 + ALPHA_BF only, real-engine DDS):

Basin	Baseline NSE	Calibrated NSE	ΔNSE	Baseline KGE	Calibrated KGE	ΔKGE	Status
usgs_01547700	0.1256	0.2107	+0.085	0.036	0.116	+0.080	PASS
usgs_03339000	0.0618	0.3192	+0.257	-0.097	0.187	+0.284	PASS

Both basins: independently verified (re-run of best solution, not calibration-loop metrics). Evidence bundle: tests/_artifacts/phase3e_readiness/real_engine_bundle_20260425/.

Note: the current canonical path is swat workflow run (see QUICKSTART.md); the lock-benchmark / locked-calibrate commands above remain valid lower-level primitives. For the current honest validation status across the basin suite, see docs/PIPELINE_RESEARCH_GRADE_AUDIT.md.

Honest caveats: NSE < 0.5 for both basins — improvement is real and verified but absolute skill is not yet benchmark-grade. Physical realism work (soil conductivity, routing) is needed before positive-skill claims. pySWATPlus bridge is non-authoritative until bridge stability is proven.

---

What this package does NOT do

• No QGIS. If you need byte-for-byte QSWATPlus parity, use QSWATPlus. We aim for numerical agreement within a few percent.
• No pySWATPlus replacement. pySWATPlus edits an existing TxtInOut and runs calibrations. swatplus-builder builds the TxtInOut. They are complementary.
• No SWAT+ engine bundled. Bring your own swatplus_exe and mount it at runtime.

---

License

MIT. See LICENSE.

Vendored: swat-model/swatplus-editor (Apache-2.0). Reference databases downloaded at install time from the ai-hydro/swatplus-reference-data mirror. pySWATPlus is GPL-3.0 and is an optional dependency — see DECISIONS.md for the licensing posture.